[Medicinal plants in the phytotherapy of alcohol or nicotine addiction. Implication for plants in vitro cultures]

Abstract

The increasing problem of nicotine and alcohol addiction, and small availability of drugs in the pharmacologic treatment causes that there are still looking for new drugs that could be used in addiction prevention and relief of withdrawal symptoms. Currently, attention has focused on a number of species possessed above mentioned pharmacological profile that do not occur naturally in moderate climate in Poland, including Passiflora incarnata, Pueraria lobata, Salvia miltiorrhiza, Salvia przewalskii. A rich source of biologically active compounds showing their possible benefit against addiction are plant derived both from its natural state as well as by biotechnological methods. Studies using in vitro plant cultures allow receiving material containing interesting secondary metabolites (active compounds) in the of shoots, root, callus and suspension cultures. Overview of pharmacological studies showed that several experiments carried out in animal models of alcoholism, and only few studies have been done on nicotine addiction using herbs. It has been shown that an extract of the herb Passiflora incarnata (and its benzoflavone derivative-BZF) can be an interesting plant material that could reduce the intensity of nicotine or alcohol withdrawal symptoms, however, only few studies have been published in this area. A larger amount of evidence has been provided to the anti-alcohol effect of the extract from the root of Pueraria lobata (kudzu). It is known that kudzu root extract is effective at reducing alcohol intake in animals and in humans. The three major isoflavones present in kudzu extracts, daidzin, daidzein and puerarin are responsible for the beneficial effects in reduction of alcohol consumption, although the exact mechanism by which kudzu suppresses ethanol intake remains to be clarified. It has been proven that daidzin in vitro is a strong, selective and reversible inhibitor of aldehyde dehydrogenase. Moreover, studies on the CNS receptor gene expression showed that the extract of kudzu possibly acts through opioid system and exhibits antagonist activity by influencing the opioid receptors mi, delta and the expression of endogenous opioid precursors (proopiomelanocortin) similarly as naltrexone. Besides kudzu, also pre-clinical data suggest that extracts from Salvia miltiorrhiza and Salvia przewalskii are effective in reducing voluntary alcohol intake in animal models of excessive alcohol drinking and their main active compounds - tanshinones and miltiron are responsible for this effect. In summary, there is a need for further studies on the mechanisms of plant extracts and their active compounds action that are valuable alternative way for the prevention and treatment of various drug dependences.